1. Field of the Invention
This invention relates to an apparatus for reducing the aerodynamic drag of a trailer truck or truck body above the cab of the vehicle attached to such body which structure is utilized as an illuminated sign for the display of a variety of indicia.
2. History of the Prior Art
Aerodynamic structures adapted for placement on truck bodies and trailer trucks above the cab are well known in the art. Examples of such are disclosed in Hersh, U.S. Pat. Nos. 4,021,069; Zelikovitz, 3,814,472; and Dempsey, 2,514,695. Attempting to reduce the aerodynamic drag of trailers or attached bodied trucks has been worked on by a number of people in various manners such as seen in Vaughn, U.S. Pat. No. 3,425,740 wherein the aerodynamic members are movable. The use of such members to reduce drag and increase the economy of the vehicle has become widespread and it is further desirable to utilize such members for advertising purpose. Such advertising associated with members on trucks is also well known and old in the art. For example, the illuminated sign of Kelly, U.S. Pat. No. 1,390,561 illustrates a sign member in front of a vehicle illuminated from the rear so that it displays the message written thereon to oncoming cars. Such signs may provide a variety of different messages such as seen in the patent to Wilson, U.S. Pat. No. 2,758,401 wherein the indicia for the left and right stop are displayed within such illuminated sign members. Also imprinting of advertising directly on truck bodies is well known and such advertising has even been utilized and affixed in such other places as on splash guards with advertising pockets as seen in the Goetz U.S. Pat. No. 3,241,857. The most pertinent patent in the prior art is FitzGerald, U.S. Pat. No. 4,135,754 wherein the aerodynamic enclosure on the truck body above the cab displays printed indicia which could be advertising material and the like which is illuminated from the rear inside the enclosure.